It is to be appreciated that any discussion of documents, devices, acts or knowledge in this specification is included to explain the context of the present invention. Further, the discussion throughout this specification comes about due to the realisation of the inventor and/or the identification of certain related art problems by the inventor. Moreover, any discussion of material such as documents, devices, acts or knowledge in this specification is included to explain the context of the invention in terms of the inventor's knowledge and experience and, accordingly, any such discussion should not be taken as an admission that any of the material forms part of the prior art base or the common general knowledge in the relevant art in Australia, or elsewhere, on or before the priority date of the disclosure and claims herein.
In prior art arrangements, a hinge is often used to ‘hang’ a door or window In other words, the hinge enables the door to move freely (open or close) by providing a pivot point about which an edge of the door can be rotated relative to a door frame or opening. The positioning of a hinge on the door or window frame also determines the height of the door or window, that is the relative spacing between the door or window frame and the door or window surface to ensure the door or window is relatively free to move. In practice, however, a person hanging a door or window will not get the door position correct, and some adjustment will be needed.
Folding doors often have several hinged panels, suspended and/or supported on roller carriages that run along a horizontal track attached to the lintel of a door frame defining an opening. Adjacent panels are typically connected by conventional hinges at their edges and are foldable between a closed configuration in which the panels align in a common plane to close an opening, and an open configuration in which the panels are stacked at one side of the opening.
It is necessary that the hinges can be adjusted to optimise the position of the door panels relative to the door frame and track to accommodate variations in the shape and alignment of the frame, track and panels during manufacture and installation.
With this in mind, various prior art hinges have been developed to incorporate mechanisms which enable adjustment of the vertical height of the door relative to the door frame, such as arrangements where the door is hung on the pivot pin.
Furthermore, existing hinges and their adjustment mechanisms can give rise to security issues, particularly when the bifold door or window is located at an exterior wall of a building. Parts of the hinge can be accessed from the exterior and manipulated or removed. Consequently, panels can be pushed out of alignment or removed to allow access into the building.
Another adjustment mechanism uses a threaded bolt. In this mechanism, the pivot pin comprises a threaded bolt (which forms a part of the pivot of the hinge) and which enables height adjustment by rotation of the threaded bolt relative to the hinge. However, it has been found that as the door is pivoted on the hinge, the threaded bolt also rotates, which has the undesirable effect of changing the height of the door as it opens and closes.
Australian patent AU-749753 (Centor Products Pty Ltd) discloses one type of adjustment mechanism comprising a pair of hinge leaves pivotally connected to a hinge pin, the upper end of the hinge pin being in threaded engagement with the carriage. The hinge pin can thus be turned clockwise or anticlockwise so that it moves along the thread to vary the distance between the hinge leaves and the carriage.
Australian patent applications AU-2013203730, AU-2013203755 and AU-2013203767 (CiiLock Engineering Pty Ltd) relate to relatively complex pivoting mechanisms for hinges, including adjustable hinges. The mechanism includes a bayonet-type locking system that is moved against a biasing means as the hinge pin is moved.